If you’ve been vaping for any amount of time, you’ll have heard someone refer to you vapour as “vape smoke,” or simply as smoke. These comments, or questions, usually come from a place of concern, but are often ignorant of what a vape actually does and what it produces. While there are plenty of visual similarities between smoke and vapor, the truth is they are vastly different in essence and should not be viewed in the same light.
Before we go in-depth on the scientific differences between the two, we’ll first look at the definitions of the words to offer a shallow explanation of the differences between vapor and smoke.
Smoke: As defined by the Merriam-Webster Dictionary, smoke is “the gaseous products of burning materials especially of organic origin made visible by the presence of small particles of carbon.” The keyword in this description is “burning” as it suggests the material must go through combustion or pyrolysis. Burning a substance drastically changes its chemical composition and produces many other chemicals as it changes the material being burned. In other words, lighting something on fire produces many other substances contained in the smoke.
Vapor: As defined by the Merriam-Webster Dictionary, vapor is “a substance in the gaseous state as distinguished from the liquid or solid state.” This definition may seem somewhat sparse, but it does explain that vapor is a substance that is simply in a gaseous state. This implies that it maintains the same molecules as its liquid or solid phase and does not undergo a change to produce new chemicals.
That being said, what is technically created by a vaporizer is an aerosol. An aerosol is generally defined as “a suspension of fine solid particles or liquid droplets in air or another gas.” This definition better explains what happens to an e-liquid in an e-cigarette, as the liquid when vaped turns into particles suspended in the air. That being said, these particles are still vastly different from smoke, as they are a liquid, rather than solid particles found in smoke.
For the sake of adhering to the terms used by the majority of vapers, we’ll continue using the term vapor when we explain what aerosol is.
The Differences Between Smoke and Vapor
To put it as simply as possible, lighting a cigarette will produce smoke, while vaporizing an e-liquid will produce a vapor. The visual similarities between the two are quite similar, but beyond that they do not have much in common. Both are very different in composition and behave in distinct ways.
Composition
When looking at tobacco and e-liquid, the only compositional similarity between the two is the presence of nicotine. While vaping is not necessarily safe, tobacco smoke contains thousands of chemicals, with 70 of them being proven carcinogens that are incredibly unhealthy to inhale.
Although some vapers often misattribute e-cigarette vapor to water vapor, the substance does not actually contain water at all. As we know, e-liquids are comprised of vegetable glycerin (VG), propylene glycol (PG), nicotine, and food grade flavourings. All of these items have been marked as “safe to ingest” by the CDC, with the exception of nicotine. While these substances have been marked as safe for ingestion, there has been no proof to indicate it is safe or unsafe in inhale.
Smell
As any smoker can attest, smoke lingers in the room for a long period of time and will often stick to many surfaces for extended periods of time. This smell is often unnoticed by heavy smokers, but non-smokers can easily recognize it for hours after a cigarette has been smoked.
While vapor clouds are often denser than smoke, and dissipate more slowly, they do not linger in terms of aroma. Aside from residual vapor in the air, there is often very little evidence that a person has vaped and there is little residue left behind.
Residue
Speaking of residue, smoking will eventually stain furniture, walls, and fabrics. This will not only create an unsightly stain, but will also leave an almost permanent aroma on the object. The residue created by smoking is often associated with the plethora of chemicals contained in a cigarette, as well as the chemicals produced after combustion.
Unlike smoking, which produces a very apparent and difficult to clean residue, vaping only leaves a slightly blurry coating on glass surfaces. This has to do with the PG and VG in vapor, but it cleans easily with basic household cleaners and will not stain fabrics or furniture.
Temperature
The average temperature of a cigarette coal rests around 1112F (600C) and can rise to 1652 F (900C) when taking a puff. While the smoke does rapidly reach room temperature when inhaled and exhaled, the coal does produce a sidestream smoke that will raise the peripheral temperature around the cigarette.
E-cigarettes, on the other hand, vaporize e-liquids at a much lower temperature. These temperatures generally do not exceed 482 F (200C), meaning the vapor is much cooler than the surrounding room.
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